1. Field of the Invention
This invention relates to a method of preparing polysubstituted acylbenzenes and more particularly to synthesizing these acylbenzenes by means of a catalyst comprising a clay.
2. Discussion of the Prior Art
When an acyl halide or equivalent is reacted with 2-bromo-1,3-dimethoxybenzene to form the corresponding acylbenzene it has been found that rearrangement products either predominate or at least are present as major contaminants when usual acylating or Friedel-Craft catalysts are employed. Such rearrangement products involve bromine migration from the 2 to 4 position, e.g., ##STR1## As reported in U.S. Patent Application Ser. No. 157,916, by George M. Shutske and Linda L. Setescak, entitled "A Method of Preparing Poly-substituted Acylbenzenes," filed June 6, 1980, a solid perfluorinated resin sulfonic acid, commercially available from E. I. DuPont de Nemours as Nafion H, is employed as an acylating catalyst in reactions between acyl halides, anhydrides, or mixtures of acids and their anhydrides and 2-bromo-1,3-dimethoxybenzene or 2-bromo-1,3-dihydroxybenzene. Such a perfluorated resin sulfonic acid functions to prevent the formation of rearrangement products when 2-bromo-1,3-dimethoxy or dihydroxybenzene is employed.